1. Field of the Invention
This invention relates to a conveyor and storage system for articles and more particularly to a system providing station-to-station movement of the articles with interim storage allowing an input rate of the articles into the system to vary with respect to an output rate from the system.
2. Description of the Prior Art
One most common form of a conveying system is a simple belt driven conveyor wherein articles are transported from one station to another. In such a conveyor, the space-time relationship between articles is constant between the load station and the unload station.
Another simple conveyor system comprises a roller conveyor including a series of freely rotatable rollers allowing articles deposited thereon to be moved manually from the one end to the other without the applying of power to the rollers. Such a conveyor is ideal where temporary storage of the article is required as, for example, to allow work to be performed on the article.
Another conveyor system provides both a driven and undriven section. Articles are carried along a driven section from a load station to an accumulation station where the article is free of its driving section. The accumulation station may accommodate a work performing means with the article reengaging with the driven section for movement after completion of the work to an unload station. Varying space-time relationships between articles are provided by using different loading patterns and by the undriven accumulation station.
Still another conveyor system arranged for movement in a closed loop and includes a plurality of rectangular pallets on which articles may be selectively loaded and unloaded. A portion of the loop is powered by a timing chain which separates and positions the pallets longitudinally to provide a regulated time-spaced relationship between articles. A remaining portion of the loop is unpowered wherein the pallets are rotated 90 degrees and placed in a stacked condition. As each new pallet arrives at an inlet end of the unpowered portion, it pushes from the exit end of the unpowered portion the last pallet deposited thereon so that it reenters the powered portion after rotating to a longitudinal position. Thus, within one closed loop two distinctly different time-space relationships between articles is created allowing distinctly different functions to be provided with respect to the articles, i.e., movement v. storage.
Another system patented by the present inventor is disclosed in U.S. Pat. No. 3,613,869 where articles are lifted from a station at one elevation to a station at another elevation by a two directional oscillating conveyor arrangement having a drum-like configuration.